1. Field of the Invention
The present invention relates generally to video devices and, more particularly, to a cursor movement system for use in providing both straight and smooth curve cursor movement in a video application having only a simple discrete-direction control.
2. Description of Related Art
There are numerous devices and software interfaces for positioning a cursor displayed on a video screen. The known cursor positioning devices range from a plurality of separate buttons, a joystick, a mouse, or a graphics tablet and pen. The latter two devices are preferred in a drawing application because the user can easily produce smooth curves with corresponding movement of the mouse or graphics pen.
However, with separate buttons or a joystick (essentially separate buttons operable with a single member), it is difficult for a user to accurately guide a video cursor through a curved path. The joystick-type of input device might best be referred to as a "discrete-direction" input device, since the user is generally limited to selecting one of a limited number of discrete directions. As has been experienced by many children attempting to draw a curve on their "Etch-A-Sketch," the best that can be hoped for is a haphazard series of stair-stepped lines.
Some years ago, Nintendo of America introduced a computer-based game system that operates with an ordinary television screen. Because Nintendo games are only provided with a pair of "discrete-direction" controllers, it is difficult to implement effective drawing programs.